The present invention relates to an anti-corrosive paint, and more particularly to an anti-corrosive polyurethane coating composition which can be applied relatively thick for providing water resisting, corrosion resisting, impact resisting and electrically insulating films.
Hitherto, coal-tar enamels, asphalt and epoxy coal tar paints have been used as anti-corrosive coating compositions. However, they are poor in low temperature characteristics such as curability, brittleness, impact resistance and flexibility. Further, epoxy coal tar paints have a good adhesion property, but have the defects that the coating efficiency and abrasion resistance are bad because the curing time is long and it is hard to coat thick.
Melt coating of polyethylene has also been made for the above purposes. However, it requires a large-scale equipment and is unfit for coating in a small amount. Also, it is difficult to adopt the melt coating onto weld zones and irregular shape portions of steel pipes at the scene of labor.
A main object of the present invention is to eliminate the above-mentioned defects of conventional anti-corrosive coating compositions.
A further object of the present invention is to provide an anti-corrosive coating composition which has excellent corrosion resistance, water resistance, impact resistance and adhesion property to metals and can be applied thick for the purpose of corrosion inhibition, water proofing, formation of impact resistant film or electric insulation.
These and other objects of the present invention will become apparent from the description hereinafter.